In a Chevy Venture, the serpentine belt is a single, continuous belt that drives several engine accessories. Instead of individual belts for each accessory (like the alternator, power steering pump, water pump, etc.), the serpentine belt wraps around a pulley on each of these components, as well as a pulley on the crankshaft. The crankshaft's rotation, powered by the engine, is thus transferred to all those other accessories via this single belt.
Essentially, it's the main drive belt for all the important non-engine-related components that keep your Venture running smoothly. If it breaks, those accessories will stop functioning.
